Solid-state drives (SSDs) are data storage devices that use solid-state memory to store data. Most SSDs use NAND-based flash memory. Because flash memory must be erased before it can be rewritten, and the memory can only be erased in larger units called blocks (made up of multiple pages), some of the data already in memory may need to be relocated and then rewritten on the flash memory in order to free up memory space for new data from the host again. This amplifying effect is known as write amplification (WA), and it increases the number of writes required over the life of the SSD. Flash memory can only be programmed and erased a limited number of times before the wear begins to deteriorate the integrity of the storage; i.e., the number of program/erase cycles, or P/E cycles, is finite. Therefore, a lower write amplification is desirable to reduce the number of P/E cycles and thereby increase the life of the SSD.